The present invention relates to wings having variable camber, and more particularly to wings having slotted trailing edge flaps that can be rotated, while in a tucked position, to vary wing camber without introducing wing surface discontinuities and drag.
The range of speeds having optimal lift to drag performance is increased by varying camber while maintaining smooth wing surfaces. Such wings use linkage assemblies located within the wing to bend flexible trailing edge surfaces longitudinally. These wings are more efficient over a greater range of cruising speeds than fixed camber wings, but are unable to increase wing chord and introduce slots within the aft portion to generate high lift during takeoffs and landings.
Slotted flaps increase wing lift during takeoffs and landings by increasing the wing's chord and camber while bleeding air from under the wing to the wing's upper, aft surface. Many types of external linkage assemblies have been developed to translate the flaps to a deployed position, but they introduce undesirable drag at cruise speeds. Nevermann et al (3,853,289) improved the prior art by providing an internal linkage assembly that does not introduce significant drag while the flaps are in a tucked position. Both external and internal linkage assemblies vary wing camber by translating the flaps aftward while opening slots within the wing. Slots substantially increase drag, and render existing slotted flap linkage assemblies undesirable for varying camber at cruise speeds.
Accordingly, it is an object of this invention to broaden optimal lift to drag performance of internal slotted flap wing asemblies by providing a device that varies wing camber while maintaining smooth wing surfaces.
Another object of this invention is to rotate slotted flaps about a flap pivot on forward flap linkage assemblies that varies wing camber without translational movement.
Another object of this invention is to provide variable camber actuator assemblies for controlling the rotational displacement of slotted flaps.
Another object of this invention is to provide flap linkage assemblies that control the position of forward and rear flaps relative to a midwing section, and operate independently from the variable camber actuators.
A further object of this invention is to provide contoured spoilers for keeping the wing surfaces smooth while slotted flaps are rotated.